Engineering Commons^™

Data-Driven Reachability Of Non-Linear Systems Via Optimization Of Chen-Fliess Series, Ivan Perez Avellaneda

Graduate College Dissertations and Theses

A reachable set is the set of all possible states produced by applying a set of inputs, initial states, and parameters. The fundamental problem of reachability is checking if a set of states is reached provided a set of inputs, initial states, and parameters, typically, in a finite time. In the engineering field, reachability analysis is used to test the guarantees of the operation’s safety of a system. In the present work, the reachability analysis of nonlinear control affine systems is studied by means of the Chen-Fliess series. Different perspectives for addressing the reachability problem, such as interval arithmetic, mixed-monotonicity, …

Pymoocfd - A Multi-Objective Optimization Framework For Cfd, George Martin Cunningham Love

Graduate College Dissertations and Theses

Modern computational resource have solidified the use of computer modeling as an integral part of the engineering design process. This is particularly impressive when it comes to high-dimensional models such as computational fluid dynamics (CFD) models. CFD models are now capable of producing results with a level of confidence that would previously have required physical experimentation. Simultaneously, the development of machine learning techniques and algorithms has increased exponentially in recent years. This acceleration is also due to the widespread availability of modern computational resources. Thus far, the cross-over between these fields has been mostly focused on computer models with low …

Optimization Of Energy-Constrained Resources In Radial Distribution Networks With Solar Pv, Mohammad Nawaf Nazir

Graduate College Dissertations and Theses

The research objective of the proposed dissertation is to make best use of available distributed energy resources to meet dynamic market opportunities while accounting for AC physics of unbalanced distribution networks and the uncertainty of distributed solar photovoltaics (PV). With ever increasing levels of renewable generation, distribution system operations must shift from a mindset of static unidirectional power flows to dynamic, unpredictable bidirectional flows. To manage this variability, distributed energy resources (DERs; e.g.,solar PV inverters, inverter-based batteries, electric vehicles, water heaters, A/Cs) need to be coordinated for reliable and resilient operation. This introduces the challenge of coordinating such resources at …

Economic Efficiency And Carbon Emissions In Mes With Flexible Buildings, Zach Lawrence Hurwitz

Graduate College Dissertations and Theses

Multi-energy systems offer an opportunity to leverage energy conversion processes and temporary energy storage mechanisms to reduce costs and emissions during operation of campuses, cities, and buildings. With increasing options for flexibility in demand-side resources it is possible to meet demand without sacrificing comfort and convenience of MES occupants.

This Thesis develops a multi-period, linear optimization model of an MES with flexible buildings that captures nonlinearities in the efficiency of energy conversion processes. The flexible buildings are parametrized, in part, based on historical data from a college campus in Vermont, USA. The idea of the MES model is to investigate …

Knee Articular Cartilage Material Properties Estimation Through Fea, Eduardo Enrique Valdez

Graduate College Dissertations and Theses

Osteoarthritis (OA) is a debilitating disease that leads to disability and loss of quality of life. Post-traumatic osteoarthritis (PTOA) is a version of OA that develops after acute injury to the knee. PTOA is of particular interest because the disease can manifest earlier in life compared to primary OA. Several studies have shown that changes in the mechanical properties of soft tissues in the knee (articulating cartilage and menisci) are associated with worsening OA grades. Changes to the tissue mechanical properties must be considered to generate realistic computational models of individuals who have suffered traumatic injuries to the knee. Therefore, …

Sparsity Constrained Inverse Problems - Application To Vibration-Based Structural Health Monitoring, Chandler B. Smith

Graduate College Dissertations and Theses

Vibration-based structural health monitoring (SHM) seeks to detect, quantify, locate, and prognosticate damage by processing vibration signals measured while the structure is operational. The basic premise of vibration-based SHM is that damage will affect the stiffness, mass or energy dissipation properties of the structure and in turn alter its measured dynamic characteristics. In order to make SHM a practical technology it is necessary to perform damage assessment using only a minimum number of permanently installed sensors. Deducing damage at unmeasured regions of the structural domain requires solving an inverse problem that is underdetermined and(or) ill-conditioned. In addition, the effects of …

Multi-Objective Optimization Mission Design For Small-Body Coverage Missions, David William Hinckley

Graduate College Dissertations and Theses

Missions concerning small-body celestial objects are of growing interest due to the resources and information they can provide. Such missions require detailed information about the surface of the body for interactions, such as landing on the surface, as well as predicting the gravity field of the object. This work provides a means of optimizing the mission elements of trajectory and imaging target schedules so that the level of knowledge of the surface can be increased. The information required to increase one's knowledge of the surface is described as a set of conditions placed on the collection of images taken of …

Optimization Of Turbulent Prandtl Number In Turbulent, Wall Bounded Flows, Donald Edward Bernard

Graduate College Dissertations and Theses

After nearly 50 years of development, Computational Fluid Dynamics (CFD) has become an indispensable component of research, forecasting, design, prototyping and testing for a very broad spectrum of fields including geophysics, and most engineering fields (mechanical, aerospace, biomedical, chemical and civil engineering). The fastest and most affordable CFD approach, called Reynolds-Average-Navier-Stokes (RANS) can predict the drag around a car in just a few minutes of simulation. This feat is possible thanks to simplifying assumptions, semi-empirical models and empirical models that render the flow governing equations solvable at low computational costs. The fidelity of RANS model is good to excellent for …

Leveraging The Information Content Of Process-Based Models Using Differential Evolution And The Extended Kalman Filter, Lucas Howard

Graduate College Dissertations and Theses

Process-based models are used in a diverse array of fields, including environmental engineering to provide supporting information to engineers, policymakers and stakeholdes. Recent advances in remote sensing and data storage technology have provided opportunities for improving the application of process-based models and visualizing data, but also present new challenges. The availability of larger quantities of data may allow models to be constructed and calibrated in a more thorough and precise manner, but depending on the type and volume of data, it is not always clear how to incorporate the information content of these data into a coherent modeling framework. In …